United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued January 9, 2007 Decided February 9, 2007
No. 01-1046
KENNECOTT GREENS CREEK MINING COMPANY,
PETITIONER
v.
MINE SAFETY AND HEALTH ADMINISTRATION AND
SECRETARY OF LABOR,
RESPONDENTS
UNITED STEEL, PAPER AND FORESTRY, RUBBER,
MANUFACTURING, ENERGY, ALLIED INDUSTRIAL AND
SERVICE WORKERS INTERNATIONAL UNION, AFL-CIO, ET AL.,
INTERVENORS
Consolidated with
01-1124, 01-1146,
05-1255, 05-1291, 05-1296, 05-1312, 05-1314,
06-1184, 06-1194, 06-1204, 06-1205, 06-1223, 06-1225
On Petitions for Review of Final Standards of the
Federal Mine Safety and Health Administration
Henry Chajet and Thomas C. Means argued the causes for
petitioners. With them on the briefs were Edward M. Green,
David Farber, Harold P. Quinn, Jr., Laura E. Beverage, John
2
K. McDonald, Michael T. Heenan, Margaret S. Lopez, and
William K. Doran. Kurt E. Blase entered an appearance.
Edward D. Sieger, Senior Appellate Attorney, U.S.
Department of Labor, argued the cause for respondent. With
him on the brief was Nathaniel I. Spiller, Assistant Deputy
Solicitor. Allen H. Feldman, Attorney, entered an appearance.
Daniel M. Kovalik and Randy S. Rabinowitz were on the
brief for intervenor United Steel, Paper and Forestry, Rubber,
Manufacturing, Energy, Allied Industrial and Service Workers
International Union.
Before: GINSBURG, Chief Judge; SENTELLE, Circuit Judge;
and EDWARDS, Senior Circuit Judge.
Opinion for the Court filed by Circuit Judge SENTELLE.
SENTELLE, Circuit Judge: Several mining industry groups
and mine operators petition for review of three Mine Safety and
Health Administration (“MSHA”) rules that regulate diesel
particulate matter (“DPM”) in underground metal and non-metal
mines. Petitioners contend that MSHA did not have sufficient
evidence that DPM presents a risk to miners’ health, that MSHA
unreasonably chose to regulate other substances as surrogates
for DPM, and that the DPM exposure limits in the new rules
cannot feasibly be achieved by mine operators. Petitioners also
assert that MSHA unlawfully granted medical evaluation and
transfer rights to workers who are required to wear respirators,
and that MSHA’s final implementation timetable was not a
logical outgrowth of the proposed rules. We find these
arguments to be without merit, and we deny the petitions for
review.
3
I.
Diesel exhaust is comprised of both gasses and particulate
matter. The challenged rules regulate only the particulate
components of diesel exhaust. Other provisions of MSHA rules,
not at issue in this case, regulate exposure to diesel exhaust
gasses. See 30 C.F.R. § 57.5001.
On January 19, 2001, MSHA promulgated rules setting
concentration limits for diesel particulate matter in underground
metal and non-metal mines.1 Diesel Particulate Matter
Exposure, 66 Fed. Reg. 5706 (2001) (“2001 Rules”). First,
MSHA conducted a risk assessment for DPM. The agency
determined that miners were exposed to very high levels of
DPM, and that this exposure can cause numerous adverse health
effects, including eye irritation, respiratory problems, and lung
cancer. Id. at 5752-5855. MSHA concluded that it was
necessary to regulate DPM exposure to protect miners from
these risks. Id. at 5855. Second, the agency determined that
there was no reliable way to measure DPM directly for
compliance purposes. Id. at 5718. Therefore, MSHA chose to
regulate total carbon (“TC”) as a surrogate for DPM. Id. at
5726-27. Total carbon was deemed to be a reliable surrogate
because there was evidence in the record that TC makes up
approximately 80-85% of DPM, and that this is a consistent
relationship. Id. In the 2001 Rules, MSHA set concentration
limits of 400 micrograms of TC (effective July 2002) and 160
1
In 2001, MSHA also promulgated rules regulating diesel
engine exhaust in coal mines. See Diesel Particulate Matter Exposure
of Underground Coal Miners, 66 Fed. Reg. 5526 (2001) (codified at
30 C.F.R. pt. 72). Those rules were not challenged, and have been in
force since 2001.
4
micrograms of TC (effective January 2006).2 Id. at 5706-07.
During the rulemaking, several commenters argued that TC was
an unreliable surrogate for DPM because it was susceptible to
interference from other organic carbon compounds, such as
tobacco smoke and oil mist. However, MSHA concluded that
it could avoid these problems by collecting samples a sufficient
distance away from possible sources of interference. Id. at
5726-30. Lastly, in its 2001 Rules, MSHA determined that mine
operators could feasibly comply with the new DPM exposure
limits. Id. at 5884-90. The agency identified numerous control
technologies that could be used to reduce DPM emissions,
including exhaust filters, environmental cabs, low-emission
engines, improved ventilation systems, low sulfur fuels, and
better training and maintenance. Id. at 5888-90.
Several parties petitioned for review of the 2001 Rules.
MSHA conceded that there were problems with the rules –
especially regarding the use of TC as a surrogate for DPM – and
agreed to conduct further research to address the problem of
interference with TC sampling. After a study of 31 mines,
MSHA, the miners’ unions, and the industry groups agreed to
several changes to the 2001 Rules. The effective date for the
400 TC interim limit was postponed until July 2003. Diesel
Particulate Matter Exposure, 67 Fed. Reg. 47,296, 47,298-99
(2002). Also, MSHA concluded that TC was an unreliable
proxy for DPM in certain circumstances, and promised to
initiate an expedited rulemaking to change the DPM surrogate
from total carbon to elemental carbon (“EC”). Id.
2
All exposure limits in MSHA’s rulemakings are expressed in
terms of micrograms per cubic meter. For simplicity, we will refer to
the limits only in terms of the exposure limit and the substance being
regulated (i.e. 160 TC instead of 160 TC µg/m3 ).
5
In a rulemaking completed in June 2005, MSHA made
several changes to its 2001 Rules. Diesel Particulate Matter
Exposure, 70 Fed. Reg. 32,868 (2005) (“2005 Rules”). Most
importantly, MSHA converted the interim DPM limit from 400
TC to 308 EC, based on a TC-to-EC conversion factor of 1.3 to
1. Id. at 32,944. This conversion factor was calculated based on
data from samples in the 31-mine study. Id. The agency
expressed confidence that this sampling and conversion
methodology “produces a reasonable estimate of TC without
interferences.” Id. However, the agency did not convert the
final limit from EC to TC – it kept that limit at 160 TC, pending
further rulemaking. Id. at 32,870. In the 2005 Rules, MSHA
also made two key changes with respect to feasibility. First, the
rules state that mine operators must require miners to wear
respirators if “controls do not reduce a miner’s exposure to the
DPM limit, controls are infeasible, or controls do not produce
significant reductions in DPM exposures.” Id. at 32,915-16.
Second, MSHA permitted mine operators to seek a one-year
renewable extension of the compliance deadline if they could
show that they were unable to meet the DPM exposure limits.
Id. at 32,951-53.
In September 2005, MSHA sought comments on several
more proposed changes to the DPM rules. Diesel Particulate
Matter Exposure, 70 Fed. Reg. 53,280 (2005) (“2005 Proposed
Rules”). The agency noted that mine operators were having
some difficulties with new filter and engine technologies, and
thus proposed extending the effective date for the final limit of
160 TC to 2011 (with a five-year graduated phase-in period).
Id. at 53,282-84, 53,288. It also proposed adding medical
evaluation and transfer rights for miners who would be forced
to wear respirators because their employers were not in
compliance with the DPM exposure limits. Id. at 53,289-90.
6
In May 2006, MSHA once again amended the DPM rules.
Diesel Particulate Matter Exposure, 71 Fed. Reg. 28,924 (2006)
(“2006 Rules”). The 2006 Rules departed from MSHA’s 2005
proposal by postponing the effective date for the 160 TC final
limit for only two years to May 2008. They also set a new
interim limit of 350 TC, effective January 2007. Id. at 28,977-
78. MSHA promised to initiate a separate rulemaking to convert
these final limits from TC to the more reliable EC. Id. at
28,983. With respect to feasibility, the agency determined that
several types of DPM control technologies were becoming more
readily available, and that mine operators could use these
technologies to meet the DPM exposure limits. Id. at 28,933-40.
The 2006 Rules also adopted the agency’s proposal to grant
medical evaluation and transfer rights to miners who must wear
respirators because the mines in which they work are not in
compliance with the DPM exposure limits. Id. at 28,986-91.
The National Mine Association, the National Stone, Sand
& Gravel Association, and several mine operators petitioned for
review of MSHA’s 2001, 2005, and 2006 rules, alleging that the
rules are arbitrary and capricious and contrary to law. The
United Steelworkers Union intervened on behalf of MSHA in
defense of the DPM rules.
II.
Petitioners first challenge MSHA’s risk assessment for
diesel particulate matter. In particular, they argue that: (1)
MSHA failed to demonstrate that DPM presents a substantial
risk to miners’ health; (2) MSHA failed to consider whether pre-
existing regulations on diesel exhaust gasses are sufficient to
protect miners from the risks of DPM; and (3) MSHA
disregarded the fact that newer engines might increase the
number of harmful “nanoparticles” in mines. We review
MSHA’s risk assessment under the Administrative Procedure
7
Act, which states that reviewing courts shall “hold unlawful and
set aside” any agency action that is “arbitrary, capricious, an
abuse of discretion, or otherwise not in accordance with law.”
5 U.S.C. § 706(2)(A). Under the arbitrary and capricious test,
we must ensure that the agency has “examine[d] the relevant
data and articulate[d] a satisfactory explanation for its action
including a rational connection between the facts found and the
choice made.” Motor Vehicle Mfrs. Ass’n v. State Farm Mut.
Auto. Ins. Co., 463 U.S. 29, 43 (1983) (internal quotation marks
omitted).
The Mine Act states that MSHA shall “develop,
promulgate, and revise as may be appropriate, improved
mandatory health or safety standards for the protection of life
and prevention of injuries in coal or other mines.” 30 U.S.C. §
811(a). Moreover, the Act states:
The Secretary, in promulgating mandatory standards
dealing with toxic materials or harmful physical agents
under this subsection, shall set standards which most
adequately assure on the basis of the best available evidence
that no miner will suffer material impairment of health or
functional capacity even if such miner has regular exposure
to the hazards dealt with by such standard for the period of
his working life. Development of mandatory standards
under this subsection shall be based upon research,
demonstrations, experiments, and such other information as
may be appropriate.
Id. § 811(a)(6)(A). Thus, before promulgating a health or safety
standard under the Mine Act, MSHA must show that the
substance being regulated presents a risk of “material
impairment of health or functional capacity” for miners who are
regularly exposed to the substance. Under the applicable
standard, courts extend deference to MSHA’s determinations as
8
to which substances present such a risk. In a case involving
MSHA’s regulation of oxygen levels in mines, we noted that
“[a]t most . . . the agency was required to identify a significant
risk associated with having no oxygen standard at all.” Nat’l
Mining Ass’n v. MSHA, 116 F.3d 520, 528 (D.C. Cir. 1997).
Moreover, we emphasized that “the Secretary was entitled to err
on the side of overprotection by setting a fully adequate margin
of safety.” Id. (internal quotation marks omitted).
Here, MSHA has adequately demonstrated that DPM
presents a significant risk to the health and safety of miners. In
the 2001 Rules, MSHA conducted an exhaustive risk assessment
that was based upon an analysis of the relevant data and
scientific literature. 66 Fed. Reg. at 5752-5855. First, the
agency cited several studies that showed that miners were
exposed to DPM at much higher levels than workers in other
occupations. Id. at 5753-64. More specifically, MSHA
determined that “median dpm concentrations observed in some
underground mines are up to 200 times as high as mean
environmental exposures in the most heavily polluted urban
areas, and up to 10 times as high as median exposures estimated
for the most heavily exposed workers in other occupational
groups.” Id. at 5764.
Next, MSHA determined that numerous adverse health
effects are causally related to heightened DPM exposure. Id. at
5764-5822. The agency identified several studies that found
links between DPM exposure and acute health effects, such as
eye irritation, decreases in pulmonary function, and bronchial
inflammation. Id. at 5767-70. More significantly, MSHA
concluded that miners who are regularly exposed to DPM will
face a heightened risk of developing lung cancer. In reaching
this conclusion, MSHA analyzed 47 epidemiological studies
(from 1957 to 1999) as well as two “meta-analyses” that
aggregated the data from the earlier studies. Id. at 5773-82.
9
“Some degree of association between occupational dpm
exposure and an excess prevalence of lung cancer was reported
in 41 of the 47 studies reviewed by MSHA.” Id. at 5775.
Moreover, the agency reasonably explained why it discounted
the findings of the six studies that did not find a causal link
between DPM exposure and lung cancer risk. Three of these
studies did not allow for a sufficiently long latency period
between exposure and evaluation, and a fourth study used too
small of a cohort. Id. at 5783. And five of the six “negative”
studies did not have statistically significant results, whereas 25
of the 41 “positive” studies did find a statistically significant
link between DPM exposure and lung cancer risk. Id. at 5785.
MSHA concluded that:
Although no epidemiologic study is flawless, studies of
both cohort and case-control design have quite consistently
shown that chronic exposure to diesel exhaust, in a variety
of occupational circumstances, is associated with an
increased risk of lung cancer. . . . With only rare
exceptions, involving too few workers and/or observation
periods too short to have a good chance of detecting excess
cancer risk, the human studies have shown a greater risk of
lung cancer among exposed workers than among
comparable unexposed workers.
Id. at 5825. We hold that MSHA corralled more than enough
evidence in support of its risk assessment, and that the agency
reasonably explained why it did not rely on the studies that cut
against its conclusions.
Petitioners argue that MSHA’s risk assessment was flawed
because the agency failed to consider whether pre-existing
limitations on diesel exhaust gasses might also provide adequate
protection against exposure to diesel particulate matter.
However, this argument ignores the fact that DPM presents
10
health risks independent of the risks posed by diesel exhaust
gasses. MSHA’s risk assessment in the 2001 Rules focused only
on the specific risks caused by exposure to diesel particulate
matter. See 66 Fed. Reg. at 5764 (noting that MSHA’s risk
assessment “reviews the various health effects . . . that may be
associated with dpm exposures”) (emphasis added). As
explained above, the agency reasonably determined that DPM
is a “toxic material or harmful physical agent” that poses a
significant risk to the health of miners. Accordingly, MSHA
was authorized by the Mine Act to promulgate exposure limits
for DPM independent of the agency’s pre-existing rules
regulating diesel exhaust gasses. See 30 U.S.C. § 811(a)(6).
Indeed, the agency emphasized that “MSHA will, of course,
continue to enforce the limits applicable to diesel gasses, but this
enforcement will be separate from the enforcement of the dpm
concentration limits under the final dpm rule.” 2001 Rules, 66
Fed. Reg. at 5856. Thus, we hold that MSHA reasonably chose
to promulgate separate rules for diesel particulate matter based
upon the agency’s determination that DPM – in its own right –
presents significant risks to the health and safety of miners that
are distinct from the health risks posed by diesel exhaust gasses.
Petitioners also assert that MSHA’s risk analysis was
flawed because it failed to take into consideration the effects of
“confounders” such as miners’ use of tobacco products.
However, in the 2001 Rules, MSHA specifically identified
eighteen published epidemiological studies that controlled for
tobacco use, five of which also controlled for asbestos exposure.
Id. at 5787. Even controlling for tobacco use, “[a]ll but one of
these 18 studies reported some degree of excess risk associated
with occupational exposure to diesel particulate, with
statistically significant results reported in eight.” Id.
Finally, petitioners contend that MSHA’s risk assessment
was arbitrary and capricious because it disregarded the fact that
11
newer, cleaner engines – which are often necessary to reduce
DPM exposure – may increase the number of dangerous
“nanoparticles” in mines. We disagree. As explained above, a
substantial body of scientific evidence has identified a
statistically significant causal connection between DPM
exposure and lung cancer risk. In contrast, the risks from
nanoparticles are currently speculative at best – in the 2001
rulemaking, MSHA noted that nanoparticles “may” be more
harmful than larger particles, but that “much more medical
research and diesel emission studies are needed to fully
characterize diesel nanoparticles emissions and their impact on
human health.” Id. at 5738. MSHA’s actions in the face of this
evidence were entirely reasonable. The agency chose to
promulgate rules immediately to regulate the known risks from
DPM, while conducting further research into the potential health
effects of nanoparticles. We cannot hold that this course of
action was arbitrary and capricious.
Under the Mine Act, MSHA is given a significant degree of
deference in its identification of substances that present
significant risks to the health and safety of miners. See Nat’l
Mining Ass’n, 116 F.3d at 527-28. Here, MSHA conducted an
exhaustive survey of the relevant evidence and concluded that
exposure to diesel particulate matter may place miners at a
heightened risk of developing lung cancer and other health
problems. We see no reason to disrupt this conclusion, and thus
we deny the petitions for review with respect to MSHA’s
threshold risk assessment.
III.
In its rulemakings, MSHA concluded that it did not have a
reliable method of measuring DPM directly at low concentration
levels. See 2001 Rules, 66 Fed. Reg. at 5718. Accordingly, the
agency chose to regulate total carbon (“TC”) and elemental
12
carbon (“EC”) as surrogates for DPM. Petitioners raise several
challenges to MSHA’s use of these surrogates. In particular,
petitioners argue that TC and EC are flawed proxies for DPM
because TC is sensitive to interference from other carbon-based
sources, and because there is no reliable and consistent method
for converting DPM to EC and TC. We agree with the
petitioners that TC and EC are not perfect substitutes for DPM.
But our standard of review under the arbitrary and capricious
test is only reasonableness, not perfection. See State Farm, 463
U.S. at 43 (requiring the agency to “articulate a satisfactory
explanation for its action including a rational connection
between the facts found and the choice made”). Additionally,
“we will give an extreme degree of deference to the agency
when it ‘is evaluating scientific data within its technical
expertise.’” Hüls Am., Inc. v. Browner, 83 F.3d 445, 452 (D.C.
Cir. 1996) (quoting Int’l Fabricare Inst. v. EPA, 972 F.2d 384,
389 (D.C. Cir. 1992)). On the record before us, we cannot hold
that MSHA acted arbitrarily and capriciously by using TC and
EC as surrogates for DPM.
At the outset, we note that there is nothing inherently
problematic with an agency regulating one substance as a
surrogate for another substance. In other areas of environmental
law, this Court has held that “[t]he EPA may use a surrogate to
regulate hazardous pollutants if it is ‘reasonable’ to do so.”
Nat’l Lime Ass’n v. EPA, 233 F.3d 625, 637 (D.C. Cir. 2000).
For example, we have upheld the EPA’s use of hydrocarbons
(“HC”) as a surrogate for fine particulate matter (“PM”),
explaining that:
EPA regulated HC emissions as a means of controlling fine
PM emissions and pollution. The Agency reasonably
determined that regulating HC would control PM pollution
both because HC itself contributes to such pollution, and
because HC provides a good proxy for regulating fine PM
13
emissions.
Bluewater Network v. EPA, 370 F.3d 1, 18 (D.C. Cir. 2004).
See also Sierra Club v. EPA, 353 F.3d 976, 985 (D.C. Cir. 2004)
(upholding the EPA’s regulation of particulate matter as a
surrogate for hazardous air particles because there were
“[s]trong direct correlations” between the surrogate and the
target substance).
In the instant case, MSHA reasonably chose to use TC as a
surrogate for DPM. Based on the results of several studies,
MSHA determined that TC “accounts for 80-85% of the total
dpm concentration when low sulfur fuel is used.” 2001 Rules,
66 Fed. Reg. at 5719. The agency also noted that the “NIOSH
5040” method of analysis measures TC with “the accuracy,
precision, and sensitivity necessary to use in compliance
sampling for dpm.” Id. at 5719-22 (noting that samples taken
pursuant to the NIOSH 5040 method meet NIOSH’s “accuracy
criterion” because they “come within 25 percent of the true TC
concentration at least 95 percent of the time”). Given that TC
and DPM were tightly correlated, and that MSHA had a reliable
method for determining the amount of TC in a sample, it was
not per se unreasonable for MSHA to use TC as a surrogate for
DPM.
However, as MSHA recognized in its 2001 Rules, TC is not
always a perfect surrogate for DPM because TC measurements
can be sensitive to interferences from other carbon-based
sources, such as oil mist and tobacco smoke. Id. at 5726-30.
Accordingly, in the 2005 Rules, MSHA converted one of the
interim DPM exposure limits from total carbon to elemental
carbon (“EC”), another surrogate for DPM that is less sensitive
to interference. See 70 Fed. Reg. at 32,871 (noting that “using
EC would impose fewer restrictions or caveats on sampling
strategy (locations and durations), would produce a
14
measurement much less subject to questions, and inherently
would be more precise”). MSHA reviewed the relevant
evidence and concluded that EC was a reliable proxy for DPM
because NIOSH research and MSHA’s laboratory tests “indicate
that DPM, on average, is approximately 60 to 80% elemental
carbon.” Id. Also, using the results of the 31-mine study,
MSHA was able to establish a TC:EC conversion factor of 1.3.
See id. at 32,889-99. MSHA obtained the 1.3 conversion factor
by taking the median of the ratios observed during sampling.
Moreover, in making these calculations, the agency only focused
on valid samples – it omitted samples that were subject to
interference. Id. at 32,944. Petitioners assert that the TC:EC
conversion ratio used by MSHA is arbitrary and capricious
because the correlation between TC and EC varies in a
statistically significant manner. However, after analyzing over
1,000 samples from various mines, MSHA found that measuring
TC directly or measuring EC and multiplying by the conversion
factor of 1.3 made no difference to finding compliance with the
400 TC limit in 93.6% of the samples. Id. at 32,876.
Obviously, the conversion factor is not perfect, and there is still
some variability in the TC:EC ratio. However, MSHA’s
decision to use the median ratio from valid samples in the 31-
mine study as the conversion factor was well within the scope of
the agency’s discretion. And MSHA’s sampling confirms that
the 1.3 conversion factor – although not perfect – is a relatively
accurate way of converting EC to TC. We cannot hold that it
was arbitrary and capricious for the agency to use EC as a
surrogate for DPM.
Finally, petitioners assert that the current interim limit of
350 TC and the final limit of 160 TC are arbitrary and capricious
because MSHA did not convert these limits from TC to EC,
even though the agency had acknowledged that TC can be an
unreliable measure of DPM. We disagree. Although MSHA
has recognized that TC is sensitive to interferences, the agency
15
has not entirely written off TC as a proxy for DPM. Indeed,
MSHA has clearly stated in its rules that TC can still serve as a
consistent and reliable surrogate for DPM as long as samples are
taken in areas away from tobacco smoke and oil mist. See 2001
Rules, 66 Fed. Reg. at 5719 (noting that cigarette smoke is
“under the control” of mine operators, and therefore it can be
prohibited during sampling periods); id. at 5729 (noting that
samples should be taken “upwind” of drilling that produces oil
mist). Moreover, MSHA has stated that it will initiate a new
rulemaking to convert the final limits from TC to EC.3 2006
Rule, 71 Fed. Reg. at 28,983. In sum, MSHA has concluded
that EC is a better proxy for DPM than TC, but this does not
automatically render the use of TC to be arbitrary and
capricious. Even though TC sampling is more difficult than EC
sampling, MSHA has reasonably determined that TC can still be
a reliable proxy for DPM as long as samples are taken in the
proper manner. In any event, MSHA’s rulemaking suggests that
it has no intention of using TC as a stand alone proxy.
Although total carbon and elemental carbon are not perfect
surrogates for DPM, MSHA reasonably concluded based on
evidence in the record that TC and EC are sufficiently well-
correlated with DPM that they can serve as reliable proxies.
These determinations are given “an extreme degree of
deference” given that they involve complex judgments about
sampling methodology and data analysis that are “within [the
agency’s] technical expertise.” Hüls Am., 83 F.3d at 452.
Accordingly, we deny the petitions for review with respect to
3
MSHA did not apply the 1.3 conversion factor to the final
limit out of concern that the TC to EC ratio may be different at the
lower level. It has, however, indicated that it will apply the 1.3
conversion factor as a check to samples measured for compliance with
the 350 TC interim limit if the rulemaking has not been completed by
that time.
16
the use of total carbon and elemental carbon as surrogates for
diesel particulate matter.
IV.
Petitioners argue that the DPM exposure limits violate the
Mine Act because they cannot feasibly be achieved by mine
operators within the time period established by MSHA’s rules.
Petitioners also contend that MSHA was too optimistic about the
efficacy of various DPM control technologies, and that the
agency changed its feasibility determinations without a reasoned
explanation. We find these arguments to be without merit.
Under the Mine Act, MSHA “shall set standards which
most adequately assure on the basis of the best available
evidence that no miner will suffer material impairment of health
or functional capacity even if such miner has regular exposure
to the hazards dealt with by such standard for the period of his
working life.” 30 U.S.C. § 811(a)(6)(A). Moreover, the Act
states:
In addition to the attainment of the highest degree of health
and safety protection for the miner, other considerations
shall be the latest available scientific data in the field, the
feasibility of the standards, and experience gained under
this and other health and safety laws.
Id. This Court has not yet analyzed the precise role of feasibility
in a Mine Act rulemaking. However, many other environmental
and worker protection statutes contain feasibility requirements,
and we can look to cases interpreting those statutes to inform
our analysis. See, e.g., 29 U.S.C. § 655(b)(5) (“Occupational
Safety and Health Act”) (stating that the Secretary of Labor shall
“set the standard which most adequately assures, to the extent
feasible, on the basis of the best available evidence, that no
17
employee will suffer material impairment of health”).
The Supreme Court has interpreted “feasible” in the OSH
Act as meaning “capable of being done, executed, or effected,”
both technologically and economically. Am. Textile Mfrs. Inst.
v. Donovan, 452 U.S. 490, 508-09 (1981). In order for its rules
to be deemed feasible, an agency must establish “a reasonable
possibility that the typical firm will be able to develop and
install engineering and work practice controls that can meet the
[permissible exposure limit] in most of its operations.” Am. Iron
& Steel Inst. v. OSHA, 939 F.2d 975, 980 (D.C. Cir. 1991)
(“AISI”) (citation omitted). Given that feasibility determinations
involve complex judgments about science and technology, our
standard of review is deferential: the agency is “not obliged to
provide detailed solutions to every engineering problem,” but
only to “give plausible reasons for its belief that the industry
will be able to solve those problems in the time remaining.”
Nat’l Petrochemical & Refiners Ass’n v. EPA, 287 F.3d 1130,
1136 (D.C. Cir. 2002). The fact that “a few isolated operations
within an industry” will not be able to comply with the standard
does not undermine a showing that the standard is generally
feasible. AISI, 939 F.2d at 980. Moreover, MSHA has
emphasized that its DPM rules are intended to be “technology
forcing,” and the industry petitioners have conceded in their
brief that MSHA has authority to promulgate technology-forcing
rules. See 2005 Proposed Rules, 70 Fed. Reg. at 53,283 (“When
we established the 2001 final limit, we were expecting some
mine operators to encounter difficulties implementing control
technology because the rule was technology forcing.”); Reply
Br. of Petitioners at 33. When a statute is technology-forcing,
the agency “can impose a standard which only the most
technologically advanced plants in an industry have been able to
achieve – even if only in some of their operations some of the
time.” United Steelworks of Am. v. Marshall, 647 F.2d 1189,
1264 (D.C. Cir. 1980) (quoting AISI v. OSHA, 577 F.2d 825,
18
832-35 (3d Cir. 1978)).
Petitioners assert that the implementation timetable
established by the 2006 Rules is not feasible, and that many
mine operators will be unable to meet the final exposure limits.
To the contrary, MSHA provided more than enough evidence to
justify its conclusion that the timetable is feasible. See 2006
Rules, 71 Fed. Reg. at 28,933-75 (summarizing evidence in
support of feasibility determinations). In the 2006 Rules,
MSHA determined that several types of DPM control
technologies were more widely available than the agency had
previously thought. For example, the agency noted that by
2005, several mines were using biodiesel fuel, which reduces
DPM emissions from diesel engines. Id. at 28,936. Similarly,
MSHA acknowledged that mine operators had problems using
filters in the past, but the agency emphasized that filters are a
highly effective tool for controlling DPM if they are properly
selected, installed, and maintained. Id. at 28,944-46. MSHA
extensively discussed the pros and cons of all currently-available
filtering technologies, and it determined that several newer
models of filters “are not subject to many of the difficult
implementation issues that have slowed the adoption of some
DPM controls.” Id. at 28,944. Moreover, MSHA stated that it
will continue to provide “extensive information” to mine
operators about the proper procedures for selecting, installing,
and maintaining their filtration systems. Id. at 28,946. In sum,
the agency concluded that “the mining industry as a whole can
reduce DPM levels to the 2001 final limit of 160 TC µg/m3 by
May 20, 2008.” Id. at 28,978. MSHA offered an abundance of
evidence in support of its feasibility determinations, and we
cannot hold that the agency’s conclusions were arbitrary and
capricious.
Petitioners also challenge MSHA’s findings about several
specific types of control technologies, especially “environmental
19
cabs” and improved mine ventilation. They argue that these
control technologies should not have been considered in
MSHA’s feasibility analysis because they have important
limitations or are only useful in certain types of mines. These
arguments misinterpret the meaning of “feasibility.” For its
rules to be upheld, MSHA does not need to show that every
technology can be used in every mine. The agency must only
demonstrate a “reasonable possibility” that a “typical firm” can
meet the permissible exposure limits in “most of its operations.”
AISI, 939 F.2d at 980. In the 2006 Rules, MSHA explained that:
As we have maintained throughout this rulemaking, mine
operators should determine the control or combination of
controls that will be best suited to their mine-specific
circumstances and conditions, and that controls need to be
evaluated, selected, and implemented on a case-by-case and
application-by-application basis.
71 Fed. Reg. at 28,942. Thus, the fact that some of the specific
control technologies identified by MSHA cannot be used in
every mine does not undermine the overall reasonableness of the
agency’s feasibility determinations. This also undercuts
petitioners’ argument that MSHA should have engaged in a
feasibility analysis for each specific type of mine. MSHA has
never suggested that there is a one-size-fits-all approach for
every mine to meet the DPM exposure limits. Rather, the
agency has reasonably concluded that many different
technologies can be effective in reducing DPM exposure, and it
is up to each individual mine operator to choose the best mix of
controls for that particular mine. Nothing in the Mine Act or the
APA requires an agency to describe in detail how every single
regulated party will be able to comply with the agency’s rules.
See, e.g., Nat’l Petrochemical & Refiners Ass’n, 287 F.3d at
1136 (noting that an agency must “identify the major steps for
improvement” but need not provide “detailed solutions to every
20
engineering problem”) (citation omitted).
MSHA’s feasibility determinations are buttressed by the
agency’s statistical findings that many mines are already in
compliance with the DPM exposure limits. In the 2006 Rules,
MSHA provided data from its prior enforcement sampling,
which revealed that 82% of samples were in compliance with
the 308 EC interim limit, 78% of samples were in compliance
with the 350 TC interim limit, and 46% of samples were in
compliance with the 160 TC final limit. 71 Fed. Reg. at 28,961.
Furthermore, the data indicated that of the mines sampled, 54%
were in compliance with the 308 EC interim limit, 45% were in
compliance with the 350 TC interim limit, and 18% were in
compliance with the 160 TC final limit. Id. Moreover, this
sampling focused on mines that were likely to have the highest
DPM exposure levels; thus, the actual industry-wide compliance
rates are likely to be higher than the compliance rates for these
samples. Id. Focusing upon the percentage of sampled mines
in compliance, petitioners contend the data demonstrates that the
imposed limits are infeasible. On the contrary, we agree with
MSHA that the data supports the agency’s conclusion that the
limits are feasible. It is not arbitrary or capricious to consider
feasible an interim limit with which half of all sampled mines
are already in compliance. And given that – in the 2006 Rules
– MSHA extended the effective date for the final limit until May
2008, mines that are not yet in compliance will still have almost
a year and a half to achieve compliance with the final limits.
Additionally, this Court has held that “[a]ny risk that the
standard may prove to be infeasible in practice is
counterbalanced by flexibility in the standard’s enforcement.”
AISI, 939 F.2d at 980. Here, MSHA’s rules allow mine
operators to seek an extension of the compliance deadline if they
are having difficulty achieving the DPM exposure limits. A
mine that “requires additional time to come into compliance”
21
because of “technological or economic constraints” may seek a
renewable one-year extension of the deadline. 30 C.F.R. §
57.5060(c). See also 2005 Rules, 70 Fed. Reg. at 32,951-53.
We also noted in AISI that an agency’s burden of proving
feasibility is “greatly ease[d]” if employers are permitted to
require employees to use respirators if the exposure limits
cannot be met by other means. 939 F.2d at 980. MSHA’s 2005
Rules contain precisely that requirement – if a mine operator is
unable to comply with the DPM exposure limits, it must provide
“respiratory protection” to miners. See 30 C.F.R. § 57.5060(d).
See also 2006 Rules, 71 Fed. Reg. at 28,986-91; 2005 Rules, 70
Fed. Reg. at 32,953-58. Thus, if any mine operators experience
difficulty complying with the DPM exposure limits, they will be
able to apply for an extension of the deadline and require their
employees to wear respirators. This “flexibility in the standard’s
enforcement” only reinforces our conclusion that MSHA’s
feasibility determinations were reasonable. See AISI, 939 F.2d
at 980.
Finally, petitioners contend that MSHA’s feasibility
determinations are arbitrary and capricious because the agency
reversed itself several times without reasoned explanation.
Contrary to petitioners’ assertions, however, MSHA did not
change its feasibility determinations between the 2005
rulemaking and the 2006 rulemaking. After promulgating the
2005 Rules, MSHA issued a set of proposed rules that would
have changed the effective date for the DPM final limit. See
2005 Proposed Rules, 70 Fed. Reg. at 53,280-93. In the
proposed rules, MSHA noted that some of its feasibility
determinations were being “questioned” and that some of its
assumptions “may not” have been valid; the agency sought
comments from the public about these issues. Id. at 53,283.
However, none of these statements can be deemed a “reversal”
of the agency’s feasibility determinations. Indeed, in the same
set of proposed rules, MSHA also stated that the final limit of
22
160 TC might still be feasible because of mine operators’ “wider
use of alternative fuels and filter technology.” Id. Thus, the
2005 Proposed Rules sought new comments from the public
about certain feasibility issues, but did not actually change any
of the agency’s feasibility determinations. It cannot be said that
the agency changed its position on these matters without
reasoned explanation.
In sum, we deny the petitions for review with respect to
MSHA’s feasibility determinations. The agency identified
several types of control technologies that are effective at
reducing DPM exposure, and it offered evidence that a
substantial number of mines are already in compliance with the
DPM limits. We see no reason to second-guess MSHA’s
conclusion that its DPM exposure limits are feasible.
V.
Petitioners also challenge MSHA’s inclusion in the DPM
rules of medical evaluation and transfer rights for workers who
are required to wear respirators. See 2006 Rules, 71 Fed. Reg.
at 28,986-91. First, petitioners assert that MSHA included these
provisions in its final rules without giving adequate notice to the
regulated parties. This argument is flatly contradicted by the
2005 Proposed Rules, in which MSHA stated:
We are interested in comments from the mining community
on whether we should include in the final rule, pursuant to
Section 101(a)(7) of the Mine Act, a provision requiring a
medical evaluation to determine a miner’s ability to use a
respirator before the miner is fit tested or required to work
in an area of the mine where respiratory protection must be
used under the final limits. In addition, we are seeking
comments on whether the final rule should contain a
requirement for transfer of a miner to an area of the mine
23
where respiratory protection is not required if a medical
professional has determined in the medical evaluation that
the miner is unable to wear a respirator for medical reasons.
70 Fed. Reg. at 53,289. MSHA also included the full text of the
proposed rules regarding medical evaluation and transfer rights.
Id. Thus, the petitioners’ contention that MSHA pulled a
“surprise switcheroo” by including these provisions in the 2006
Rules is groundless.
Petitioners also contend that MSHA lacked statutory
authority to adopt the medical evaluation and transfer
requirements. The Mine Act expressly permits MSHA to
require medical evaluations and transfers “where appropriate.”
30 U.S.C. § 811(a)(7). In the 2006 Rules, MSHA reasonably
concluded that such provisions were “appropriate.” With
respect to medical evaluations, MSHA relied upon an OSHA
study that found that “use of a respirator may place a
physiological burden on a worker while wearing such a device.”
71 Fed. Reg. at 28,986. Given that respirators could potentially
cause “illness, injury, and in some instances, even death,”
MSHA reasonably concluded that miners should be provided
with medical examinations before they are required to wear
respirators. Id. at 28,986-87. Similarly, MSHA determined that
it was “appropriate” to require transfers with pay protection for
workers who are physically unable to wear respirators (but only
to an “existing” job, not a new position). Id. at 28,987-91. If
the rules did not provide transfer rights, miners might attempt to
wear respirators – despite the risks of doing so – in order to
protect their jobs. Id. at 28,990. MSHA reasonably concluded
that the transfer rights would “remove the fear of reprisals” for
such workers. Id. Petitioners argue that MSHA was required to
do a full cost-benefit analysis before it could grant medical
evaluation and transfer rights. However, the Mine Act contains
no such requirement – it only requires that these provisions be
24
“appropriate.” MSHA easily met its burden of showing the
appropriateness of these provisions.
***
Finally, petitioners argue that in the 2006 Rules MSHA
impermissibly reduced the length of the phase-in period for the
final exposure limits from what was proposed in 2005. We find
this contention to be without merit because MSHA’s final
implementation timetable was a “logical outgrowth” of the
proposed rules. At the time the proposed rules were issued in
2005, the final DPM limit of 160 TC was scheduled to go into
effect in January 2006. In the proposed rules, MSHA sought
comments about whether the agency should “stagger the
effective dates for implementation of the final DPM limit,
phased-in over a five year period” between 2006 and 2011. 70
Fed. Reg. at 53,288. The proposed rules also stated:
We request comments on whether five years is the correct
timeframe for reducing miners’ exposures to the 160
micrograms of TC as originally established in the 2001
standard and to have been effective in January 2006.
Id. In the 2006 Rules, MSHA ultimately chose an effective date
of May 2008 for the final limit. 71 Fed. Reg. at 28,978. This
choice essentially splits the difference between the original
effective date (January 2006) and the proposed effective date
(January 2011). This Court has found the “logical outgrowth”
test to be satisfied in similar circumstances. In Husqvarna v.
EPA, 254 F.3d 195, 203 (D.C. Cir. 2001), we held that a four-
year phase-in period for certain EPA rules was “a logical
outgrowth of the proposed five-year implementation schedule.”
Just so here. We hold that the final two-year phase in period for
the 160 TC final limit was a logical outgrowth of the proposed
five-year phase in period.
25
VI.
For the aforementioned reasons, we deny the petitions for
review in their entirety. MSHA’s risk assessment was based
upon evidence in the record that workers who are exposed to
high levels of DPM face increased risks of lung cancer and other
adverse health effects. The agency’s selection of total carbon
and elemental carbon as surrogates for DPM was based upon
evidence that TC and EC are closely correlated with DPM and
that there are reliable conversion ratios between DPM, TC, and
EC. And MSHA offered more than enough evidence in support
of its conclusion that mine operators can feasibly comply with
the DPM exposure limits. Our standard of review is deferential,
and we can find nothing in the administrative record that would
justify second-guessing the agency’s conclusions. The petitions
for review are therefore
Denied.